Anesthetic Preconditioning of the Small Intestine in Hemorrhagic Hypotension

Abstract

Aim of the study. To investigate the preconditioning effect of sevoflurane on small intestinal mucosa in experimental hemorrhagic hypotension.Material and methods. The study was performed on a cohort of 106 male rats that included two experimental groups: one exposed to ether (Group 1, n=40) and another one exposed to sevoflurane (Group 2, n=40); two control groups included 20 intact animals, of which 10 were anesthetized with ether and 10 with sevoflurane. Six animals were excluded from the study because they died by the 2nd hour of hemorrhagic hypotension under ether anesthesia. The study parameters were measured at 15 min, 30 min, 1 h, and 2 h of hemorrhagic hypotension. Amylolytic activity of the small intestine mucosa was determined by E. A. Zabelinsky, B. W. Smith and I. M. Roe technique modified by A. M. Ugolev. The data were statistically analyzed using the nonparametric Mann-Whitney method.Results. By 15 min of hemorrhagic hypotension, the activity of amylase fractions in all small intestine regions in Group 2 animals was significantly lower vs the Group 1 rats. By 30 min of hemorrhagic hypotension, the activity of the enzyme fractions in all small intestine regions in Group 2 animals remained significantly lower than in Group 1, by an average of 2 to 9 times (P=0.01; P<0.001), and after 1 h of hemorrhagic hypotension, it was 2 and 4 times lower (P=0.02; P<0.001). By the 2nd hour of hemorrhagic hypotension, the activity of nearly all duodenal amylase fractions in the Group 2 animals remained 3-4 times lower compared to Group 1. Meanwhile, a significantly higher activity of slowly desorbing and intracellular amylase fractions vs the control group was observed in jejunum and ileum.Conclusion. In hemorrhagic hypotension under sevoflurane anesthesia, a decrease of the pancreas excretory function, stabilization of the brush border of the mucosa of all small intestine regions, including enterocyte membranes, was found during the first hour of experiment. Two hours after the hemorrhage, the biochemical evidence of brush border damage in the jejunum and ileum was revealed.